Input-capable display device

ABSTRACT

An input-cable display device is provided including a first substrate on which a pair of electrodes that drive a liquid crystal layer are provided; a second substrate wherein the liquid crystal layer is formed within an inner surface of the second substrate between the first substrate and the second substrate; a detection electrode and a dielectric film that are laminated on an outer surface of the second substrate; a detector; a light shielding film; and a color filter layer, wherein the pair of electrodes provided on the first substrate comprises a pixel electrode and a common electrode, and the light shielding film and the color filter layer are laminated on the inner surface of the second substrate.

CROSS REFERENCES TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 15/177,840, filed on Jun. 9, 2016, which application is acontinuation of U.S. patent application Ser. No. 14/723,073, filed onMay 27, 2015, which application is a continuation of U.S. patentapplication Ser. No. 11/957,047, filed on Dec. 14, 2007, issued as U.S.Pat. No. 9,069,401 on Jun. 30, 2015, which claims priority to JapanesePriority Patent Application JP 2007-019138 filed in the Japan PatentOffice on Jan. 30, 2007, the entire content of which is herebyincorporated by reference.

BACKGROUND 1. Technical Field

The present invention relates to an input-capable display device, suchas, for example, a touch panel, to which an input function is added.

2. Related Art

In recent years, as a compact information electronic apparatus, such asa personal digital assistants (PDA) or a personal computer spreads, adisplay device that has added a so-called touch panel function, which isused for input operation by bringing an object, such as a finger or apen, into contact with a display screen, has been widely used. In such atouch panel, there is an electrostatic capacitance method as a methodfor detecting a position at which a finger, or the like, contacts, whichis, for example, described in Japanese Unexamined Patent ApplicationPublication No. 2006-146895 and Japanese Unexamined Patent ApplicationPublication No. 2003-196023. The electrostatic capacitance method is amethod that flows a weak electric current through an electrostaticcapacitance formed by touching a display surface with user's finger andthereby detects a position of contact on the basis of the amount ofelectric current. Here, in the electrostatic capacitance method, adetection electrode formed in a planar manner and a dielectric filmlaminated on the detection electrode are used. By touching thedielectric film with the finger, an electrostatic capacitance is formed.

In a liquid crystal display device with a touch panel function that usesthe above electrostatic capacitance method, there is a problem that,when an electric field generated by a driving signal that is suppliedbetween a pair of electrodes for driving a liquid crystal layer reachesthe detection electrode, the accuracy of detection of a position ofcontact is decreased because this electric field component acts as anoise. Here, in the above liquid crystal display device with a touchpanel function, it is attempted to remove a noise generated due to asignal that is generated from a driving signal.

In the above existing liquid crystal display device with a touch panelfunction, however, the following problem still remains. That is, in theexisting liquid crystal display device with a touch panel function,there is a problem that it. requires a complex system for generating asignal that removes a noise.

SUMMARY

An advantage of some aspects of the invention is that it provides aninput-capable display device, which is capable of suppressing aninfluence of noise without requiring a complex system.

An aspect of the invention employs the following configuration to solvethe problems. That is, an aspect of the invention provides aninput-capable display device. The input-capable display device includesa first substrate, a second substrate, a detection electrode, adielectric film, and a detector. A pair of electrodes that drive aliquid crystal layer are provided on the first substrate. The secondsubstrate is opposed to the first substrate through the liquid crystallayer. The detection electrode and the dielectric film are laminated onan outer surface of the second substrate. The detector detects aposition at which an electrostatic capacitance is formed with thedetection electrode through the dielectric film. The second substrateincludes a shield conductor that is formed on a side adjacent to theliquid crystal layer. An electric potential of the shield conductor isfixed.

According to the above aspect of the invention, by providing the shieldconductor in the second substrate on the side adjacent to the liquidcrystal layer, an influence of noise that is generated due to a drivingsignal of the liquid crystal layer is suppressed without excessivelythickening the second substrate and without using a complex system, thusimproving the accuracy of detection of a position of contact on thedisplay surface. That is, by supplying a driving signal of the liquidcrystal layer to the pair of electrodes, an electric field that isgenerated to be directed toward the second substrate is blocked by theshield conductor. For this reason, it is possible to prevent a couplingbetween the pair of electrodes and the detection electrode. Here, thepair of electrodes that drive the liquid crystal layer are provided inthe first substrate, and a sufficient distance is ensured between thepair of electrodes and the shield conductor. Therefore, the strength ofelectric field that is generated by the driving signal of the liquidcrystal layer and directed toward the shield conductor is small ascompared with the case where a vertical electric field mode electrodestructure is employed. Thus, the shield conductor effectively blocks theelectric field. Accordingly, without providing an additional complexsystem and without excessively thickening the second substrate, acoupling between the pair of electrodes and the detection electrode isprevented and thereby an influence of noise due to the driving signal issuppressed. In addition, by forming the shield conductor integrally withthe second substrate to not excessively thicken the second substrate, itis possible to ensure a sufficient transmittance ratio. Furthermore,because the shield conductor and the detection electrode aresufficiently spaced apart from each other, it is possible to prevent acapacitance component from being formed between the shield conductor andthe detection electrode.

In the input-capable display device according to the aspect of theinvention, the shield conductor may have translucency. According to theabove aspect of the invention, because the shield conductor is formed ofa translucent conductive material, it is possible to form a shieldconductor in a planar shape, and it is possible to reliably suppress aninfluence of noise due to a driving signal of the liquid crystal layer.

In the input-capable display device according to the aspect of theinvention, the shield conductor may constitute a light shielding film.According to this aspect of the invention, because the shield conductoralso serves as a light shielding film, the thickness of the secondsubstrate is reduced.

In the input-capable display device according to the aspect of theinvention, the dielectric film may constitute a polarizer. According tothis aspect of the invention, because the polarizer is formed by using adielectric material, the number of components is reduced and thethickness of the input-capable display device is reduced.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

The invention will be described with reference to the accompanyingdrawings, wherein like numbers reference like elements.

FIG. 1 is a schematic cross-sectional view that shows an input-capableliquid crystal display device according to a first embodiment of theinvention.

FIG. 2 is an equivalent circuit diagram of FIG. 1.

FIG. 3 is a plan configuration diagram that shows a sub-pixel region.

FIG. 4 is a cross-sectional view that is taken along the line IV-IV inFIG. 3.

FIG. 5 is a perspective view that shows a mobile personal computer.

FIG. 6 is a cross-sectional view that shows an input-capable liquidcrystal display device according to a second embodiment of theinvention.

DETAILED DESCRIPTION

First Embodiment

A first embodiment of an input-capable display device according to theinvention will now be described with reference to the accompanyingdrawings. Note that the scales of the drawings used in the followingdescription are appropriately changed in order to make the components berecognizable. Here, FIG. 1 is a schematic cross-sectional view thatshows the input-capable liquid crystal display device. FIG. 2 is anequivalent circuit diagram of FIG. 1. FIG. 3 is a plan configurationdiagram that shows a subpixel region. FIG. 4 is a cross-sectional viewthat is taken along the line IV-IV in FIG. 3.

Input-Capable Display Device

The input-capable liquid crystal display device (input-capable displaydevice) 1 is a transmissive color liquid crystal display device, inwhich a single pixel is constituted of three sub-pixels that outputcolored rays of R (red), G (green), B (blue). Here, a display area thatbecomes a minimum unit for forming display is termed as “sub-pixelregion”. Here, a display area that becomes a minimum unit for formingdisplay is termed as “sub-pixel region”.

First, the schematic configuration of the input-capable liquid crystaldisplay device 1 according to the present embodiment will be described.The input-capable liquid crystal display device 1 according to thepresent embodiment, as shown in FIG. 1, includes an element substrate(first substrate) 11, which is an active matrix substrate, an oppositesubstrate (second substrate) 12 that is opposed to the element substrate11, and a liqu.id crystal layer 13 that is held between the elementsubstrate 11 and the opposite substrate 12. The input-capable liquidcrystal display device 1 is configured to irradiate illuminating lightfrom the outer surface side (the side away from the liquid crystal layer13) of the element substrate 11. In addition, the input-capable liquidcrystal display device 1 includes a seal material 14, which issubstantially rectangular and box-shaped in plan view, provided at theouter peripheral portion of an opposed area in which the elementsubstrate 11 is opposed to the opposite substrate 12. By this sealmaterial, the element substrate 11 and the opposite substrate 12 areadhered to each other. Then, an image display area is formed inside theseal material 14 within the input-capable liquid crystal display device1. Furthermore, the input-capable liquid crystal display device 1includes a detection electrode 15 that is provided on the outer surfaceside {the side away from the liquid crystal layer 13) of the oppositesubstrate 12, a polarizer 16 that is provided on the outer surface sideof the element substrate 11, a polarizer (dielectric film) 17 that isprovided on the outer surface side of the detection electrode 15, and adetector 18 that detects a position of electrostatic capacitance formedwith the detection electrode 15 through the polarizer 17.

A plurality of sub-pixel regions are arranged in the image display areaof the input-capable liquid crystal display device 1 in a matrix, asshown in FIG. 2. In each of the plurality of sub-pixel regions, a pixelelectrode (first electrode) 21 and a TFT (thin film transistor) element22 that is used for switching the control of the pixel electrode 21 areformed. In addition, in the image display area, a plurality of datalines 23 and a plurality of scanning lines 24 are arranged in a grid.The sources of the TFT elements 22 are connected to the correspondingdata lines 23, the gates thereof are connected to the correspondingscanning lines 24, and the drains thereof are connected to thecorresponding pixel electrodes 21.

The data lines 23 are configured to supply image signals S1, S2, . . .Sn that are supplied from a driving circuit (not shown), which isprovided in the input-capable liquid crystal display device 1, to thecorresponding subpixel regions. Here, the data lines 23 may beconfigured to supply the image signals S1 to Sn sequentially in theorder of lines or may be configured to supply the image signals S1 to Snin units of a plurality of the grouped data lines 23 that are arrangedadjacent to each other. The scanning lines 24 are configured to supplyscanning signals G1, G2, . . . Gm, which are supplied from a drivingcircuit (not shown) provided in the input-capable liquid crystal displaydevice 1, to the corresponding sub-pixel regions. Here, the scanninglines 24 supply the scanning signals G1 to Gm in a pulse-like manner inthe order of lines at a predetermined timing.

In addition, the input-capable liquid crystal display device 1 isconfigured so that, as the TFT element 22, which is a switching element,is made into an on state only during a certain period because of theinput of the scanning signals G1 to Gm, the image signals S1 to Snsupplied from the data lines 23 are written to the pixel electrodes 21at a predetermined timing. Then, predetermined levels of image signalsS1 to Sn that are written to the liquid crystal through the pixelelectrodes 21 are maintained during a certain period between the pixelelectrodes 21 and common electrodes (second electrode) 43, which will bedescribed later.

A detailed configuration of the input-capable liquid crystal displaydevice 1 will now be described with reference to FIG. 3 and FIG. 4. Notethat the opposite substrate 12 is not shown in FIG. 3. Note that theopposite substrate 12 is not shown in FIG. 3. In addition, in FIG. 3,the long axis direction of the substantially rectangular sub-pixelregion in plan view is defined as X axis direction and the short axisdirection is defined as Y axis direction. The element substrate 11, asshown in FIG. 4, includes a substrate body 31, a base protection film32, a gate insulating film 33, a first interlayer insulating film 34, asecond interlayer insulating film 35, a third interlayer insulating film36 and an alignment layer 37. The substrate body 31 is formed of atranslucent material, such as glass, quartz or plastic, for example. Thebase protection film 32, the gate insulating film 33 1 the firstinterlayer insulating film 34, the second interlayer insulating film 35,the third interlayer insulating film 36 and the alignment layer 37 aresequentially laminated on the inner surface of the substrate body 31(the side adjacent to the liquid crystal layer 13). In addition, theelement substrate 11 includes a semiconductor layer 41, a scanning line24, a data line 23, a connection electrode 42, a common electrode 43,and a pixel electrode 21. The semiconductor layer 41 is arranged on theinner surface of the base protection film 32. The scanning line 24 isarranged on the inner surface of the gate insulating film 33. The dataline 23 and the connection electrode 42 are arranged on the innersurface of the first interlayer insulating film 34. The common electrode43 is arranged on the inner surface of the second interlayer insulatingfilm 35. The pixel electrode 21 is arranged on the inner surface of thethird interlayer insulating film 36.

The base protection film 32 is, for example, formed of a translucentsilicon oxide, such as SiO2 (oxide silicon), for example, and covers thesubstrate body 31. Note that the material of the base protection film 32is not limited to SiO2, but it may be formed of an insulating material,such as SiN (silicon nitride), SiON (silicon oxynitride), or ceramicsthin film. The gate insulating film 33 is, for example, formed of atranslucent material, such as SiO2, for example, and is provided tocover the semiconductor layer 41 that is formed on the base protectionfilm 32. The first interlayer insulating film 34 is, for example, formedof a translucent material, such as SiO2, and is provided to cover thegate insulating film 33 and the scanning line 24 that are formed on thegate insulating film 33. The second interlayer insulating film 35 is,for example, formed of a translucent material, such as acrylic, and isprovided to cover the first interlayer insulating film 34 and also coverthe data line 23 and the connection electrode 42 that are formed on thefirst interlayer insulating film 34. The third interlayer insulatingfilm 36 is, for example, formed of a translucent material, such as SiN,and is provided to cover the common electrode 43 that is formed on theinner surface of the second interlayer insulating film 35. The alignmentlayer 37 is, for example, formed of a resin material, such as polyimide,and is provided to cover the pixel electrode 21 that is formed on thethird interlayer insulating film 36. In addition, an alignment processis treated on the surface of the alignment layer 37 so that the shortaxis direction (Y axis direction) of the sub-pixel region shown in FIG.3 is made as an alignment direction.

As shown in FIG. 3 and FIG. 4, the semiconductor layer 41 has asubstantially L-shape in plan view and is formed to include portion ofan area that overlaps the scanning line 24 in plan view through the gateinsulating film 33. Then, a channel region 41 a is provided on an areaof the semiconductor layer 41, which overlaps the scanning line 24 inplan view through the gate insulating film 33. In addition, thesemiconductor layer 41 includes a source region 41 b and a drain region41 c that are formed by injecting impurity ion therein. Thus, the TFTelement 22 is formed using the semiconductor layer 41 as a main body.Note that the channel region 41 a is formed by not injecting impurityion into polysilicon. Here, the semiconductor layer 41 may be formed asa LDD structure in which a high concentration region that has arelatively high impurity concentration in the source region and thedrain region and a low concentration (LDD (Lightly Doped Drain)) regionthat has a relatively low impurity concentration are formed.

The scanning line 24 is arranged along the short axis direction (Y axisdirection) of the substantially rectangular sub-pixel region in planview. The scanning line 24 is, for example, formed of a metal material,such as Al (aluminum). In addition, portion of the scanning line 24,which is opposed to the channel region 41 a through the gate insulatingfilm 33, functions as the gate electrode. The data line 23 is arrangedalong the long axis direction (X axis direction) of the sub-pixel regionin plan view. The data line 23 is, for example, formed of a metalmaterial, such as Al. In addition, the data line 23 is connected to thesource region 41 b of the semiconductor layer 41 through a contact holeH1 that extends through the gate insulating film 33 and the firstinterlayer insulating film 34. That is, the data line 23 connects theTFT elements 22 that are arranged along the X axis direction. Theconnection electrode 42 is connected to the drain region 41 c of thesemiconductor layer 41 through a contact hole H2 that extends throughthe gate insulating film 33 and the first interlayer insulating film 34.

The common electrode 43 is formed to cover the second interlayerinsulating film 35. The common electrode 43 is, for example, formed of atranslucent conductive material, such as ITO (indium tin oxide). Then,an opening 43 a is formed at a portion of the common electrode 43, whichis located in proximity to a contact hole H3, which will be describedlater, that is used to conduct the pixel electrode 21 with theconnection electrode 42 in order to ensure electrical insulation againstthe pixel electrode 21. In addition, the common electrode 43 is, forexample, applied with a signal that switches periodically between apredetermined certain voltage and 0 V, or applied with a signal thatswitches periodically (every frame period or every field period) betweena first predetermined certain potential and a second predeterminedcertain potential that is different from the first predetermined certainpotential, which are used for driving the liquid crystal layer 13.

As shown in FIG. 3 and FIG. 4, the pixel electrode 21 has asubstantially ladder shape in plan view and is, for example, formed of atranslucent conductive material, such as ITO, as well as the commonelectrode 43. Then, the pixel electrode 21 includes a rectangularframe-shaped frame portion 21 a in plan view and a plurality of stripeportions 21 b that extend in the substantially short axis direction (Yaxis direction) of the sub-pixel region and are arranged at intervals inthe long axis direction (X axis direction) of the sub-pixel region.

The frame portion 21 a is formed so that two pairs of stripe electrodesare connected so as to form a substantially rectangular frame shape inplan view. Two pairs of opposite sides respectively extend along thelong axis direction (X axis direction) and along the short axisdirection (Y axis direction). In addition, the frame portion 21 a isconnected to the connection electrode 42 through the contact hole H3that extends through the second interlayer insulating film 35 and thethird interlayer insulating film 36. In this way, the pixel electrode 21is connected to the drain of the TFT element 22. The stripe portions 21b are formed so as to be parallel to each other. Both ends of eachstripe portion 21 b are connected to the frame portion 21 a at portionswhich extend along the Y axis direction. In addition, the stripeportions 21 b are provided so that the extending directions of thestripe portions 21 b are not parallel to the Y axis direction. That is,the extending direction of each of the stripe portions 21 b is formed sothat each strip portion 21 b approaches the scanning line 24 as itextends from one end adjacent to the data line 23 to the other end awayfrom the data line 23 in plan view. As described above, theinput-capable liquid crystal display device 1 is configured so that avoltage is applied between the stripe portions 21 b and the commonelectrode 43 and then the liquid crystal is driven by an electric field(lateral electric field) that is generated in a direction in which theplane of the substrate extends. In this way, the pixel electrode 21 andthe common electrode 43 constitute a FFS (Fringe-Field Switching) modeelectrode structure.

On the other hand, as shown in FIG. 4, the opposite substrate 12includes a substrate body 51, a shield electrode (shield conductor) 52,a light shielding film 53, a color filter layer 54 and an alignmentlayer 55. The substrate body 51 is, for example, formed of a translucentmaterial, such as glass, quartz or plastic. The shield electrode 52, thelight shielding film 53, the color filter layer 54 and the alignmentlayer 55 are sequentially laminated on the inner surface of thesubstrate body 51 (the side adjacent to the liquid crystal layer 13).The shield electrode 52 is formed entirely on the inner surface of theopposite substrate 12. The shield electrode 52 is, for example, formedof a translucent conductive rr1aterial, such as ITO. Then, the shieldelectrode 52 overlaps the pixel electrode 21 and the common electrode 43through the liquid crystal layer 13. Here, the shield electrode 52 has asheet resistance of 1 kΩ/sq or below, for example. In addition, theshield electrode 52 is ensured to be conducted with a wiring portion(not shown), which is provided on the element substrate 11 through aninter-substrate conductive material (not shown), which is formed of aconductive material at the end portion of the opposite substrate 12.Then, the shield electrode 52 exhibits a substantially constantpotential through this wiring portion.

The light shielding film 53 is formed in a substantially grid in planview in a region in which, of the surface of the shield electrode 52,the edge portion of the sub-pixel region overlaps the TFT element 22,the data line 23 and the scanning line 24 through the liquid crystallayer 13 in plan view. The light shielding film 53 edges the subpixelregion. In addition, the color filter layer 54 is arranged at a positioncorresponding to each sub-pixel region so as to cover the lightshielding film 53. The color filter layer 54 is, for example, formed ofacrylic and contains a color material corresponding to the color thesub-pixel region displays. The alignment layer 55 is, for example,formed of a translucent resin material, such as polyimide and isprovided so as to cover the color filter layer 54. Then, a rubbingprocess in the same direction as the alignment direction of thealignment layer 55 is treated on the inner surface of the alignmentlayer 55.

Because the alignment process in which the short axis direction (Y axisdirection) of the sub-pixel region is defined as an alignment directionis performed for the alignment layers 37, 55, liquid crystal moleculesthat forms the liquid crystal layer 13 are aligned horizontally alongthe Y axis direction when no voltage is applied between the pixelelectrode 21 and the common electrode 43, that is, in an off state. Inaddition, liquid crystal molecules are aligned along the directionperpendicular to the extending directions of the stripe portions 21 bwhen voltage is applied between the pixel electrode 21 and the commonelectrode 43, that is, in an on state. Thus, in the liquid crystal layer13, by using a birefringent characteristic on the basis of a differencein alignment state of liquid crystal molecules between an off state andan on state, a phase difference is given to light that is transmittedthrough the liquid crystal layer 13.

The detection electrode 15 is formed entirely over the outer surface ofthe opposite substrate 12. The detection electrode 15 is, for example,formed of a translucent conductive material, such as ITO. In addition,terminal portions (not shown) are provided at respective four corners ofthe substantially rectangular detection electrode 15 in plan view. Theterminal portions are supplied with a detection signal from the detector18.

The polarizer 16 is, for example, formed so that a film formed by usinga dielectric material of polyvinyl alcohol (PVA) as a base. Then, thepolarizer 16 is provided so that the polarization axis thereof extendsalong the long axis direction (the X axis direction shown in FIG. 2) ofthe sub-pixel region. The polarizer 17 as well as the polarizer 16 isformed so that a film of polyvinyl alcohol (PVA) is used as a base. Notethat a protection film (not shown) that protects the polarizer 17 may beprovided on the outer surface side of the polarizer 17. Then, thepolarizer 17 is provided so that the polarization axis thereof extendsalong the short axis direction (the Y axis direction shown in FIG. 2) ofthe sub-pixel region. Thus, the polarizers 16, 17 are provided so thattheir polarization axes are substantially perpendicular to each other.Here, a quarter wavelength plate may be arranged on the inner side ofthe polarizer 17. By arranging the quarter wavelength plate, it ispossible to prevent ambient light that enters from the outer surface ofthe polarizer 17 from being reflected on the element substrate 11 toexit outside. Note that, in coordination with the quarter wavelengthplate, the polarization axis of the polarizer 17 is changedappropriately. In addition, an optical compensation film (not shown) maybe arranged on one of or both of the inner side of the polarizers 16,17. By arranging the optical compensation film, it is possible tocompensate for a phase difference of the liquid crystal layer 13 whenthe input-capable liquid crystal display device 1 is viewed obliquely.Also, it is possible to increase the contrast by reducing a leakage oflight. The optical compensation film employs a medium that combines anegative uniaxial medium and a positive uniaxial medium or a biaxialmedium having refractive indices of nx>nz>ny for respective directions.

The detector 18 is configured to generate a uniform electric fieldwithin the plane of the detection electrode 15 by applying the terminalportions provided on the detection electrode 15 with alternatingvoltages having the same phase and same potentials. In addition, thedetector 18 is configured to detect a position of contact of a finger,or the like, through a measured value of the magnitude of electriccurrent that flows through an electrostatic capacitance formed with thedetection electrode 15 through the polarizer 17.

Operation of Input-capable Liquid Crystal Display Device

The operation of the above configured input-capable liquid crystaldisplay device 1 will now be described. Light entering from the outersurface side of the element substrate 11 is converted by the polarizer16 to a linearly polarized light that is parallel to the long axisdirection (X axis direction shown in FIG. 3) of the sub-pixel region andthen enters the liquid crystal layer 13. Here, when it is in an offstate, the linearly polarized light that has entered the liquid crystallayer 13, owing to the liquid crystal layer 13, exits from the liquidcrystal layer 13 in the same polarized state as it was when entered theliquid crystal layer 13. Then, this linearly polarized light, becauseits polarized direction is perpendicular to the polarization axis of thepolarizer 17, is blocked by the polarizer 17 and/hence, the sub-pixelregion appears to be a dark display. On the other hand, when it is in anon state, the linear light that has entered the liquid crystal layer 13is given a predetermined phase difference (½ wavelength) by the liquidcrystal layer 13 and is converted to a linearly polarized light that hasa polarized direction perpendicular to the polarized direction when itentered the liquid crystal layer 13 and then exits from the liquidcrystal layer 13. Then, this linearly polarized light, because itspolarized direction is parallel to the polarization axis of thepolarizer 17, is transmitted through the polarizer 17 to be viewed as adisplay light and, hence, the sub-pixel region appears to be a brightdisplay.

At this time, when image signals S1 to Sn are supplied from the datalines 23 to the liquid crystal layer 13, electric fields are generatedbetween the pixel electrodes 21 and the corrunon electrodes 43 that areformed on the element substrate 11. Here, a sufficient gap is formedbetween the pixel electrodes 21 and common electrodes 43 and the shieldelectrode 52 that is provided in the opposite substrate 12.Therefore/the strength of electric fields that become noise, travelingfrom the pixel electrodes 21 and common electrodes 43 toward the shieldelectrode 52 due to the supply of the image signals S1 to Sn becomessmall as compared with a so-called vertical electric field modeelectrode structure, such as a TN mode, for example, in which the commonelectrode is provided in the opposite substrate. Thus, the electricfields that travel from the pixel electrodes 21 and common electrodes 43toward the detection electrode 15 are effectively blocked by the shieldelectrode 52.

Then, when user's finger touches the polarizer 17 in a state where auniform alternating voltage is applied within a plane of the detectionelectrode 15, an electrostatic capacitance is formed between thedetection electrode 15 and the finger through the polarizer 17. Thus,electric current flows from the terminal portions provided on thedetection electrode 15 through the electrostatic capacitance. Thedetector 18 detects the magnitude of electric current that flows by theformation of electrostatic capacitance through, for example, the fourcorners of the detection region, respectively, and then detects aposition of contact of the finger, or the like, from those pieces ofinformation. Here, because the substrate body 51, and the like, isprovided between the detection electrode 15 and the shield electrode 52and a sufficient gap is formed therebetween, a capacitance component isprevented to be formed between the detection electrode 15 and the shieldelectrode 52.

Electronic Apparatus

The above configured input-capable liquid crystal display device 1 isused as a display portion 101 of a mobile personal computer 100, asshown in FIG. 5, for example. This mobile personal computer 100 includesthe display portion 101 and a main body portion 103 that has a keyboard102.

As described above, according to the input-capable liquid crystaldisplay device 1 in the present embodiment, by providing the oppositesubstrate 12 with the shield electrode 52, an influence of noisegenerated while driving the liquid crystal layer 13 is suppressedwithout excessively thickening the opposite substrate 12 and withoutusing a complex system, thus improving the accuracy of detection of aposition of contact on the display surface. Furthermore, a sufficientdistance is ensured between the pixel electrodes 21 and commonelectrodes 43 and the shield electrode 52, so that an influence of noisegenerated while driving the liquid crystal layer 13 is small as comparedwith the case where a vertical electric field mode electrode structureis employed. Thus, the shield electrode 52 effectively blocks the noise.Then, because the shield electrode 52 and the detection electrode 15 aresufficiently spaced apart from each other, no capacitance component isformed between the shield electrode 52 and the detection electrode 15.Moreover, the shield electrode 52 is formed of a translucent conductivematerial, such as ITO, and the shield electrode 52 may be formed in aplanar shape, so that it is possible to reliably block a noise. Inaddition, because the polarizer 17 is formed by using a dielectricmaterial, the number of components is reduced.

Second Embodiment

A second embodiment of an input-capable liquid crystal display deviceaccording to the invention will now be described with reference to thedrawings. Here, FIG. 6 is a cross-sectional view that shows a sub pixelregion. Note that, in the present embodiment, because the configurationof the sub-pixel region differs from that of the first embodiment, thispoint will be specifically described. The same reference numerals areassigned to the components described in the above embodiment, and adescription thereof is omitted.

In the input-capable liquid crystal display device 110, as shown in FIG.6, a light shielding film (shield conductor) 112 that is provided in anopposite substrate 111 is formed of a conductive material and alsoserves as a shielding conductor. That is, the opposite substrate 111includes the substrate body 51, the shield electrode 112, the colorfilter layer 54 and the alignment layer 55. The light shielding film112, the color filter layer 54 and the alignment layer 55 aresequentially laminated on the inner surface of the substrate body 51.The light shielding film 112 is, for example, formed of a metalmaterial, such as Cr (chrome), having a light absorption characteristicor a conductive material, having a light absorption characteristic, thatis formed by dispersing carbon black in a resin. Then, the lightshielding film 112 is connected to the wiring portion provided theelement substrate 11 through the above described inter-substrateconductive member at the end portion of the opposite substrate 12. Thus,an electric potential of the light shielding film 112 is controlled to acertain potential. Note that the light shielding film 112 has an openingportion that is formed in correspondence with the sub-pixel region;however, an electric field that is generated due to signals supplied tothe pixel electrodes 21 so as to be directed from the pixel electrodes21 and common electrodes 43 toward the detection electrode 15 can beblocked sufficiently.

As described above, even with the input-capable liquid crystal displaydevice 110 in the present embodiment, the same function and advantageouseffects as those of the above described embodiment are obtained;however, because the light shielding film 112 also serves as a shieldconductor, the number of components is reduced and thickness of theopposite substrate 111 is reduced.

Note that the invention is not limited to the embodiments describedabove, but it may be modified into various forms without departing fromthe spirit of the invention. For example, the potential of the shieldelectrode is fixed by conducting the shield electrode to the elementsubstrate through the inter-substrate conductive member provided at theend portion of the opposite substrate; however, another method may beemployed as long as the potential of the shield electrode is fixed. Inaddition, the polarizer provided on the outer surface side of theopposite substrate constitutes a dielectric film; however, a dielectricfilm may be separately provided in addition to the polarizer.

In addition, the input-capable liquid crystal display device isconfigured so that the pixel electrodes and the common electrodes havethe FFS mode electrode structure; however, it may employ anotherelectrode structure that uses a so-called horizontal electric fieldmode, such as IPS (In-Plane Switching) mode. Then, the input-capableliquid crystal display device is a transmissive liquid crystal device;however, it may be a configuration of another liquid crystal displaydevice, such as a reflective liquid crystal display device or atransflective liquid crystal display device. Furthermore, it is notlimited to a color liquid crystal display device.

Moreover, the electronic apparatus that is provided with theinput-capable liquid crystal display device is not limited to the mobilepersonal computer, but it may be another electronic apparatus, such as acellular phone, a PDA (Personal Digital Assistants), a personalcomputer, a laptop personal computer f a workstation, digital stillcamera, an on-board monitor, a car navigation system, a heads-updisplay, digital video camera, a television; a viewfinder type or directview type video tape recorder a pager, a personal organizer, anelectronic calculator, an electronic book; a projector, a wordprocessor, a video telephone, a POS terminal, and devices provided witha touch panel display.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. A display device comprising: afirst substrate including a pair of electrodes provided thereon, thepair of electrodes comprising a pixel electrode and a common electrode;a second substrate opposed to the first substrate; a liquid crystallayer provided between the first substrate and the second substrate; apolarizer provided on an outer portion side of second substrate, theouter portion side being opposite to a liquid crystal layer side of thesecond substrate; a light shielding film having conductivity; and acolor filter layer, wherein an electric potential of the light shieldingfilm is fixed, wherein the light shielding film and the color filterlayer are stacked on the liquid crystal layer side of the secondsubstrate in order of the light shielding film and the color filterlayer from the side of the second substrate toward the liquid crystallayer, and wherein the color filter layer covers the entire lightshielding film.
 2. The display device according to claim 1, wherein thepair of electrodes constitute a horizontal electric field modestructure.
 3. The display device according to claim 1, wherein the pairof electrodes are arranged on different layers.
 4. The display deviceaccording to claim 1, wherein the light shielding film has a sheetresistance of 1 kΩ/sq or below.
 5. The display device according to claim1, wherein the light shielding film is arranged above a thin filmtransistor element that is used for switching the control of the pixelelectrode.
 6. The display device according to claim 1, furthercomprising a detection electrode arranged between the polarizer and thesecond substrate.
 7. The display device according to claim 1, whereinthe pixel electrode and the common electrode are translucent.
 8. Thedisplay device according to claim 3, wherein the pixel electrode is areflective electrode.
 9. A display device comprising: a first substrateincluding a pair of electrodes provided thereon, the pair of electrodescomprising a pixel electrode and a common electrode; a second substrateopposed to the first substrate; a liquid crystal layer provided betweenthe first substrate and the second substrate; a dielectric film providedon an outer portion side of the second substrate, the outer portion sidebeing opposite to a liquid crystal layer side of the second substrate; alight shielding film having conductivity; and a color filter layer,wherein an electric potential of the light shielding film is fixed,wherein the light shielding film and the color filter layer are stackedon the liquid crystal layer side of the second substrate in order of thelight shielding film and the color filter layer from the side of thesecond substrate toward the liquid crystal layer, and wherein the colorfilter layer covers the entire light shielding film.
 10. The displaydevice according to claim 9, wherein the pair of electrodes constitute ahorizontal electric field mode structure.
 11. The display deviceaccording to claim 9, wherein the pair of electrodes are arranged ondifferent layers.
 12. The display device according to claim 9, whereinthe light shielding film has a sheet resistance of 1 kΩ/sq or below. 13.The display device according to claim 9, wherein the light shieldingfilm is arranged above a thin film transistor element that is used forswitching the control of the pixel electrode.
 14. The display deviceaccording to claim 9, further comprising a detection electrode isarranged between the dielectric film and the second substrate.
 15. Thedisplay device according to claim 9, wherein the pixel electrode and thecommon electrode are translucent.
 16. The display device according toclaim 11, wherein the pixel electrode is a reflective electrode.
 17. Adisplay device comprising: a base substrate including a pair ofelectrodes provided thereon, the pair of electrodes comprising a pixelelectrode and a common electrode; a cover layer above the firstsubstrate; a polarizer provided on an outer portion side of the coverlayer, the outer portion side being opposite to the base substrate sideof the cover layer; and a light shielding film having a conductivityarranged above a thin film transistor element that is used for switchingthe control of the pixel electrode, wherein an electric potential of thelight shielding film is fixed, and wherein the pixel electrode issurrounded by the light shielding film.
 18. The display device accordingto claim 17, further comprising a detection electrode arranged betweenthe polarizer and the cover layer.
 19. The display device according toclaim 17, further comprising a display function layer provided betweenthe pixel electrode and the common electrode.
 20. The display deviceaccording to claim 19, wherein a predetermined voltage for displaying animage is supplied between the pixel electrode and the common electrode.